The parent invention relates to teatcup liners for use in a teatcup assembly for milking a mammal.
As known in the prior art, a plurality of teatcups are connected to respective teats suspending from the udder of a mammal such as a cow. Each teatcup assembly has a teatcup liner or inflation around a respective teat and defining a milk flow passage within the liner below the teat, and a pulsation chamber outside the liner between the liner and the teatcup shell, for example U.S. Pat. Nos. 4,269,143, 4,530,307, 5,178,095, 5,218,924, 6,055,931, all incorporated herein by reference. The system has a milking cycle with an on portion and an off portion. Milk flows from the teat towards a milking claw during the on portion, and then to a storage vessel. During the off portion, the liner is collapsed around the teat, to aid in the circulation of body fluids. Vacuum is continuously applied to the milk flow passage within the liner. Vacuum is alternately and cyclically applied to the pulsation chamber between the liner and the teatcup shell, to open and close the liner, all as is known.
The parent invention provides a liner series or family enabling the dairyman selectivity in choosing between the trade-off of liner slip versus milk harvest and milking speed. During continuing development efforts, various relationships have been discovered between various liner parameters, and in accordance therewith, a liner series has been developed having at least one and preferably a plurality of parameters which vary liner to liner in optimized manner to afford the noted selectivity.
In a further aspect of the parent invention, a particularly cost effective manufacturing method is provided for producing the liner series.
The present invention arose during continuing development efforts, including related to the noted parent invention. The present invention provides various teatcup liner constructions for desirably controlling collapse of the teatcup liner.